The present invention relates generally to the field of communications, and more particularly, to a system and method for optical bidirectional communication.
Current communications systems and networks are becoming faster and more complex, using any one of number of mediums. Communication using these systems and networks is typically bidirectional in that signals are exchanged between two sources as they communicate for various purposes. More recently, fiber optic networks have been employed as the medium for communications. Typically, the optical fibers themselves may be very small and, consequently, coupling various devices to the optical fibers to create a communications link can be difficult and expensive.
An additional problem with current optical fiber communications systems is that optical fibers are often used for unidirectional communications. This is due in part to the difficulty of physically transmitting and receiving an optical signal on a single optical fiber that may be, for example, a single micron thick. Unfortunately, this results in the need for two optical fiber links to establish bi-directional communications.
The present invention provides a bi-directional optical link and method to facilitate bi-directional optical communications with a single optical fiber. Briefly described, the bi-directional optical link comprises a thin film detector having an upper surface facing a predetermined direction to receive incident light. Also, the link includes a thin film emitter stacked over the upper surface and oriented to direct a beam of light toward the predetermined direction. The thin film detector is relatively wide and flat, where the thin film emitter can be placed on the thin film detector while occluding only a portion of the thin film detector. Thus, the thin film detector can receive incident light from a single optical fiber facing the emitter/detector from the predetermined direction while at the same time emitting a beam of light into the same single optical fiber.
The present invention can also be viewed as providing a method for establishing a bi-directional communications link. In this regard, the method can be broadly summarized by the steps of positioning a thin film detector having an upper surface so as to face a predetermined direction to receive incident light, stacking a thin film emitter over the upper surface, and, orienting the thin film emitter to direct a beam of light toward the predetermined position.
Other features and advantages of the present invention will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional features and advantages be included herein within the scope of the present invention.